Joints/ Tendons

Question 1

Components of Joint

Answer 1

1. Articular cartilage -White, smooth, glistening
2. Bone synovial membrane
3. Synovial fluid

Question 2

How does articular cartilage obtain nutrients?

Answer 2

• No nerves, blood, or lymph

- Obtain nutrients from synovial fluid & subchondral vessels

Question 3

Articular capsule is composed of…

Answer 3

Outer layer = CT
Inner layer = Synovial membrane
-A cells = Macrophages (activated by IL15)
-B cells = Fibroblasts –> produce synovial fluid

Question 4

Articular cartilage response to injury

Answer 4

• Limited response due to lack of blood flow
  1. Cartilage erosion (not reaching subchondral bone) –possible recovery
  2. Cartilage Ulceration (complete loss) –> repair w/ fibrocartilage!

Question 5

Pathogenesis of injured cartilage

Answer 5

• Lack of compression/relaxation cycle –> atrophy

- Roughened –> fibrillation –> erosion –> Eburnation (ulceration)

Question 6

Eburnation

Answer 6

Complete loss of cartilage

-exposed subchondral bone

Question 7

Pathogenesis of Inflammatory joint degeneration

Answer 7

A cells secrete IL1 & TNFalpha –> stimulate B cells to produce PG & NO & collagenases –> inhibit proteoglycan synth –> articular cartilage degeneration

Question 8

Which hormones have an anabolic effect on joints?

Answer 8

1. IL6
2. IGF
3. TNF beta

Question 9

Synovial membrane response to injury

Answer 9

1. Hyperplasia of synoviocytes
2. Pannus
3. Joint Mice
4. Osteophytes
5. Inflammatory leukocytes

Question 10

Response of Subchondral bone to injury

Answer 10

1. Sclerosis (decrease resorp/increased production)

2. Eburnation

Question 11

Pannus

Answer 11

Granulation tissue –> Ankylosis

Ankylosis = adhesion between to bones –> stiffen/immobilize joint

Question 12

Joint Mouse

Answer 12

Fragment of chondral/ osteochondral material, free in joint cavity

Question 13

Osteophytes

Answer 13

Chondro-osseous proliferations at synovial membrane / perichondrial jnx

Question 14

Joint ( portal of entry / Defense mechanisms )

Answer 14

• -Direction inoculation &/or extension by adj tissue
• -hematogenous

Defense = limited regeneration –> degenerative joint dz

Question 15

Tendons ( portal of entry / Defense mechanisms )

Answer 15

• -Lacerations or punctures
• -extension from adj infection

Defense = similar inflammatory rxn to other tissue

Question 16

Arthrogryposis

Answer 16

• contracture of the joint
• congenital
  
  • sporadic
  • viral (BLUETONGUE)
  • hereditary
• ***CNS lesion –> degeneration/atrophy of muscles –> contraction of limbs
• • non-neurologic form
• Alkaloids –lupine/ poison hemlock
• -> fetal paralysis

Question 17

Hip dysplasia

Answer 17

-Heritable –Dogs, Hereford cattle

Question 18

Synovitis

Answer 18

Inflammation of synovial membrane

Question 19

Arthritis

Answer 19

Inflammation of articular cartilage

Question 20

Osteoarthritis

Answer 20

NONinflammatory Jt Dz

aka DJD

Question 21

Arthropathy

Answer 21

Any type of Jt Dz

Question 22

Outcome of inflammation in Jt

Answer 22

1. Resolution

2. DJD

Question 23

Synovial fluid response (Acute/subacute/chronic)

Answer 23

Acute
-Reduced viscosity

Subacute
-WBCs &fibrin in fluid

Chronic

• granulation tissue
• fibrosis
• ulceration/hypertrophy of synovial lining

Question 24

“Rule of thumb” for bacterial arthritis

Answer 24

Gram + –> Pyogenic

Gram - –> Fibrinous

Question 25

Rare viral arthritis

Answer 25

Reovirus - Chickens

CAE - Goats

Question 26

Rheumatoid arthritis

Answer 26

• Autoimmune

- non-infectious

Question 27

Gout

Answer 27

Deposit of urates in /around joint

• -> acute/chronic granulomatous synovitis
• -> degeneration of articular cartilage

Question 28

Pseudogout

Answer 28

Deposits of Ca & Phos in soft tissue of synovial capsule & ligaments
-young dogs

Question 29

Outcome of IVDD

Answer 29

1. Disk herniation

2. Spondylosis –lateral & ventral –> decrease mobility/stabilztes

Question 30

Joint neoplasm

Answer 30

Synovial sarcoma
-neoplasia of synovial cells in joints/tendons

A-cells = higher chance of mets
B-cells = lower change to metastasize